The use of various data reading aids has been known for a number of years. Those confronted with the task of working with pages of numerical or other data from which specific information must be read have found it difficult to read and use such data.
For example, it is known that bookkeepers and accountants, when confronted with large pages of rows and columns of data, often find it difficult to accurately study and extract the desired figures from such rows and columns because of the need to constantly check to see if one is in the proper row or column containing the desired information.
The problems of accurately reading data have been greatly increased over the years as nearly all professions and students now use and study some form of computer printout data which consists of a large number of rows and columns of numerical or other data, only certain parts of which are desired to be used for the particular work or study project involved.
The prior art patents which have attempted to address such problems are as follows: U.S. Pat. Nos. 2,871,816 (McConnell); 3,739,739 (Brase); 4,024,831 (Sperling); 3,408,977 (Colman); 3,269,752 (Lindaman). Each of the above patents have devised means for displaying an entire row or an entire column of data. For example, the U.S. Pat. Nos. 3,739,739 and 4,024,831 show a conventional ruler having a transparent portion in the middle thereof for the purpose of displaying an entire row of numbers on a large data sheet. The problem in use of such items is that the person must be constantly rechecking to be sure of obtaining data from the desired column. The other patents cited (U.S. Pat. Nos. 2,871,816; 3,408,977; and 3,269,752) also provide a central portion for displaying an entire row or column of data. In these three patents, the entire ruler is placed on a sliding or adjustable member so that the user of the device can relocate the ruler to another entire row or column as desired. Thus, since an entire row or column is displayed, recurring errors arise. For example, in the Colman patent an entire column is displayed by the adjustable ruler but, to extract isolated data, one would have to constantly check to be sure that the proper data row is being read.
One patent which has sought to solve the above problems is that to Natoli, U.S. Pat. No. 2,892,437. The Natoli patent provides a structure which masks or covers up the portions of a row of data which are not desired to be read or copied. In the Natoli structure, small fingers extend from the outer edge of a ruler and can be adjusted to mask data which is not desired to be read. There is no central viewing aperture in Natoli so that the data row being read is not effectively isolated and highlighted relative to the rest of the data on a page. In addition, the Natoli patent shows a usage of a relatively great number of small component parts making manufacture and assembly of the device very costly.
In use, the Natoli structure is also unwieldy and time consuming. For example, in a row containing twelve numbers, a user wishing to view only three of the figures in the row would have to cover up or mask nine figures to accomplish the task. For most business and study users, it would be less time consuming and simply easier to uncover desired data columns than to cover up or mask undesired data columns. This is because, for most applications, less than half of the data in a row is desired to be copied or studied.
The sliding fingers of the Natoli patent are also subject to being jostled or bumped out of the desired masking position as the ruler is touched or moved by one using it to read or copy data from a large sheet such as a computer printout or bookkeeping form.
It can therefore be seen that it would be extremely useful in the data viewing art to provide an assembly which allows limited line viewing, i.e. permits only a portion of a row or column to be read or studied, without the disadvantages inherent in a structure such as that taught by U.S. Pat. No. 2,892,437.
Accordingly, it is an object of the present invention to provide a limited line viewing assembly which allows the limited data viewed to be effectively isolated from the remaining numbers on a large data sheet.
It is a further object of this invention to provide a limited line viewer which may be easily and economically manufactured by using a relatively smaller number of component parts while still performing the desired advantageous functions.
It is a further object of the present invention to provide a limited line viewer having component parts which are easily retained in the desired viewing or covering position so that slight movement or bumping of the device does not change the desired reading position or the component parts.
It is a further object of the present invention to provide a data viewing assembly having smaller component parts which cannot be easily separated from the main housing thereby helping to prevent loss of such component parts or injury to others by reason of separated component parts.
These and other objects and advantages of the present invention will be apparent to those of skill in the art in the detailed description set forth herein.